I've got a question regarding a SQL-select-query: The table contains several columns, one of which is an Integer-column called "size" - the task I'm trying to perform is query the table for the sum of all rows (their values), or to be more exact get a artifical column in my ResultSet called "overallSize" which contains the sum of all "size"-values in the table. Preferable it would be possible to use a WHERE-clause to add only certain values ("WHERE bla = 5" or something similar).
我有一个关于SQL-select-query的问题：该表包含几个列，其中一列是一个名为“size”的整数列 - 我正在尝试执行的任务是查询表中所有的总和行（它们的值），或更确切地说，在我的ResultSet中获取一个名为“overallSize”的人工列，其中包含表中所有“大小”值的总和。优选地，可以使用WHERE子句仅添加特定值（“WHERE bla = 5”或类似的东西）。
The DB-engine is HSQLDB (HyperSQL), which is compliant to SQL2008.
数据库引擎是HSQLDB（HyperSQL），它符合SQL2008。
Thank you in advance :)
先谢谢你 ：）
3 个解决方案
#1
10
SELECT SUM(size) AS overallSize FROM table WHERE bla = 5;
#2
9
It's not as simple as this, is it?
它不是这么简单，是吗？
SELECT SUM(SIZE)
FROM Table
WHERE bla = '5'
#3
1
Are you looking for:
你在找：
SELECT SUM(Size) FROM MyTable WHERE bal = '5'
You can also (in MSSQL)
你也可以（在MSSQL中）
SELECT Size, COl1, COl2 FROM MyTable WHERE bla ='5' COMPUTE SUM(Size)
#1
10
SELECT SUM(size) AS overallSize FROM table WHERE bla = 5;
#2
9
It's not as simple as this, is it?
它不是这么简单，是吗？
SELECT SUM(SIZE)
FROM Table
WHERE bla = '5'
#3
1
Are you looking for:
你在找：
SELECT SUM(Size) FROM MyTable WHERE bal = '5'
You can also (in MSSQL)
你也可以（在MSSQL中）
SELECT Size, COl1, COl2 FROM MyTable WHERE bla ='5' COMPUTE SUM(Size)